It has heretofore been customary to convert an image of lower spatial resolution into an image of higher spatial resolution and display the converted image. For conversion of the image, more items of image data are inter-polated (generated) from image data of lower spatial resolution.
If image data of lower spatial resolution comprises component signals of R, G, B, for example, then it has been the conventional practice to interpolate the image data independently with respect to the component signals.
Specifically, it has been customary to generate image data of R which is of higher spatial resolution from image data of R which is of lower spatial resolution, image data of G which is of higher spatial resolution from image data of G which is of lower spatial resolution, and image data of B which is of higher spatial resolution from image data of B which is of lower spatial resolution.
As a result, the efficiency has been poor, and a good level of accuracy could not been achieved.